Heat exchanger



Patented Dec. 8, 1936- HEAT EXCHANGER Robert E. Burk, Cleveland, Ohio, assignor to The Standard Oil Company,v

corporation of Ohio No Drawing.

Cleveland, Ohio, a

Application July 30, 1934,

Serial No. 737,597

2 Claims.

This invention relates to heat exchangers and more particularly heat exchangers combustion engines. These structures are un der a serious handicap of having to transfer enormous quantities of heat across relatively limited surfaces, with water which is generally unsuitable. Furthermore, engines which cannot cool properly have an increased tendency'to knock. Anything which will increase the transfer rate is accordingly fundamentally important and h hly, desirable.

To the accomplishment of the foregoing and related ends, the invention,.then, comprises the features hereinafter fully described, and. particularly pointed out in the'claims, the following description setting forth in detail certain illustrative embodiments of the invention, these being indicative however, of but a few of the various ways in which the principle of the invention may be employed.

In accordance with my invention, there is added to the circulating cooling water in the radiator and engine-jacket passages of an internal combustion engine an amount of an ionizable alkali metal meta-phosphate, such as sodium meta-phosphate. general from to 1000 parts per million, depending somewhat upon the water used. The salt is best dissolved in the entire quantity of the cooling-water before it is filled into the radiator, or for convenience in some cases, particularly where smaller amounts are used. and

the fluid circulation is very active, it may be added in concentrated solution, or sufflciently of internal The amount may range inslowly in dry form that proper solution in the cooling-water occurs. Such salt solution raises the heat-transfer coeflicient so that the heat from the engine-combustion is more efficiently transferred from the cylinder walls to the solution in the'cylinder jackets, and at the same time the meta-phosphate acts on lime and magnesia present, preventing and removing surface-coating thereby. The solution may be operated as a continuously-employed radiator-system 1o cooling fluid particularly where in lower concen-- trations, or where desired, it may be employed intermittently, alternating with runs on water without such addition.

Other modes of applying the principle of the invention may be employed, change being made as regards the details described, provided the features stated in any of the following claims, or the equivalent of such, be employed.

I therefore particularly point out and distinct- 1y claim as my invention:- A

1. Method of cooling heat exchanger systems in internal combustion engines which comprises circulating cooling fluid therethrough having an addition of sodium meta-phosphate in quantities sufllcient to'effectively increase the coefficient ofheat transference.

2. Method of cooling heat exchanger systems in internal combustion engines which comprises circulating cooling fluid therethrough having an 

